The present invention relates to technology for detecting swaps that occur between links during image transmission by the dual-system.
In the field of image transmission, images are subdivided and then transmitted. Japanese Unexamined Patent Publication No. 2000-350213 and Japanese Unexamined Patent Publication No. Hei08 (1996)-336113 for example disclose systems for subdividing an image into field images (images in an odd-numbered line and images in an even-numbered line) and then transmitting these field images.
In digital monitors such as for liquid crystal panels, both JEITA (Japan Electronics and Information Technology Industries Association) and VESA (Video Electronics Standards Association) provide standardized technology for subdividing images contained within video, into images comprised of pixels in odd-numbered positions, and images comprised of pixels in even-numbered positions and transmitting these images in parallel (Chapter 6 in JEIDA-59-1999 Digital Monitor Interface Standards Version 1.0, “Data transmission standardization criteria 2a LVDS”, Chapter 5 in VESA TV Panels Standard Version 1, Mar. 10, 2006, “LVDS Data/Color Mapping”).
The transmission system established in the above standards is from hereon called the “dual-link system” in the following description. Moreover, images comprised of pixels in odd-numbered positions are called “odd images” and images comprised of pixels in even-numbered positions are called “even images”.
Odd-numbered position pixels are pixels arrayed horizontally in odd-numbered pixel positions such as “First”, “Third”, “Fifth”, etc. Even-numbered position pixels are pixels arrayed horizontally in even-numbered pixel positions such as “Second”, “Fourth”, “Sixth”, etc.
An overview of transmitting images by the dual-link system using a single horizontal line as an example is described next while referring to FIG. 10. Here, “pixels” to which an odd number is attached indicate pixels in an odd-numbered position, and “pixels” to which an even-number is attached indicated pixels in an even-numbered position as shown in FIG. 10. The same nomenclature is utilized in each of the following drawings.
As shown in FIG. 10, image data in a single horizontal line comprised of a “pixel 1, pixel 2, pixel 3, . . . , pixel 6, . . . ” is subdivided on the transmission side into odd images comprised of pixels in odd-numbered positions (pixel 1, pixel 3, pixel 5, . . . ) and even images comprised of pixels in even-numbered positions (pixel 2, pixel 4, pixel 6, . . . ). These odd pixels and even pixels are transmitted in parallel utilizing a link 1 and a link 2.
On the receiving side these odd images and even images transmitted by way of the link 1 and the link 2 are combined and restored to the original image.
In the drawing in FIG. 11, reference numerals have been added to the drawing 7.1 on page 32 of JEIDA-59-1999 Digital Monitor Interface Standards Version 1.0. FIG. 11 shows the structure of an LDI (LVDS Display Interface) that conforms to the dual-link system.
This interface transmits two-channel image data of 24 bits each (red, green, blue at 8 bits each on two-channels) 48 bits, and horizontal and vertical synchronization signals, and data enable signals on the transmitter side as serial data on an eight-channel LVDS signal. On the receiver side, the eight-channel LVDS transmission data is converted to parallel data, and output as two-channel image data (red, green, blue at 8 bits each on two-channels) 48 bits, and horizontal and vertical synchronization signals, and data enable signals.
A graphics controller 10 subdivides the image into odd images and even images and outputs them to the interface (solid arrow lines in FIG. 10). An LCD panel 20 combines the odd images and the even images that were sent from the interface (dotted line arrows in FIG. 10) and displays them.